Though "Mountbatten-Windsor" is technically the royal family's last name, it's rarely the one members of the family use in everyday life

What’s in a royal last name?

Prince William and Prince Harry may be brothers, but their children probably won’t share a surname.

Though “Mountbatten-Windsor” is technically the royal family’s last name, it’s rarely the one members of the family use in everyday life. For example, William and Harry went by William Wales and Harry Wales during their own school days, as well as their years in the armed forces. Why? Because their father, Prince Charles, is the Prince of Wales. It’s an homage to their father’s title for occasions when “Prince” just feels a bit too formal.

When Prince George started school, it was announced that he wouldn’t be known as “His Royal Highness” in the classroom. Instead, he’ll use his father’s title as the Duke of Cambridge (mom Kate Middleton is known as the Duchess of Cambridge) and be George Cambridgein school records and to his peers and teachers.

Since Harry and Meghan Markle received the titles of Duke and Duchess of Sussex upon their marriage, it makes sense to assume that their children – starting with their newborn son – continue with the tradition and will likely use “Sussex” as their moniker.

First Annual Royal Foundation Forum
Prince Harry, Meghan Markle, Kate Middleton and Prince William
| Credit: Chris Jackson - WPA Pool/Getty

Bestowing titles to members of the royal family on their wedding day is a longtime tradition. When Prince Andrew and Sarah “Fergie” Ferguson tied the knot, the Queen made them the Duke and Duchess of York (the title that once belonged to the Queen’s own father before he became King George VI.) It’s not always dukedoms that she hands out: When Prince Edward married Sophie Rhys-Jones in 1999, they became the Earl and Countess of Wessex.

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The royals became the House of Windsor in 1917 — previously the House of Saxe-Coburg and Gotha. The switch was prompted by anti-German feelings in the United Kingdom following World War I, so they changed the name to the more-English Windsor. The family became the House of Saxe-Coburg and Gotha after Queen Victoria married Prince Albert, who was German, so the name did have German roots.

Prince William and Prince George
| Credit: Richard Pohle/The Times/PA Wire

The addition of Prince Philip to the family brought about another name change, this one, the addition of Mountbatten, the last name he adopted after giving up his title of Prince of Greece and Denmark. The name belongs to his maternal grandparents — it’s the English translation of their German name, Battenberg. The change took sometime to make its way into the royal family — 1960, to be exact, 13 years after Philip married the then-Princess Elizabeth, and eight years after she became Queen. However, this didn’t change the name of the House of Windsor, but rather just the surnames that those in said house would use when they weren’t using the style of His or Her Royal Highness (or if they’re members of the family but don’t get said style).